As is known, today the need for deployable structures, able to follow curvilinear trajectories, is particularly felt. Said need is particularly felt, for example, in the biomedical field, where probes are required able to follow curved trajectories inside the human body, or in the field of contactless inspections.
In greater detail, the need is felt for deployable structures which can be operated in such a way that the desired trajectory is followed not only by a distal end of the structure, but also by the body of the structure, as it is deployed. In other words, it is desirable for the proximal sections of a deployable structure to follow the same trajectory as the one followed previously by the distal portions; generally, this capacity is referred to as follow-the-leader, i.e. the distal end, or also as shape-keeping, i.e. the trajectory followed by the distal end. Furthermore, it is desirable for the follow-the-leader capacity to be intrinsic to the deployable structure, i.e. not exploit the characteristics of the environment in which the structure operates.
For example, the patent application EP2446803 describes an articulated robotic probe, which includes a first and a second mechanism arranged concentrically, each of which can be directed in desired directions; furthermore, each mechanism comprises a plurality of rigid cylindrical arms, interconnected by means of spherical joints, and is controlled alternatively in a first mode, in which it is rigid as a whole, and in a second mode, in which the arms are mobile with respect to one other.
The robotic probe according to the patent application EP2446803 is intrinsically of the follow-the-leader type, however its capacity for faithfully following a predetermined trajectory is limited, since it is of the articulated type. Furthermore, when one of the two mechanisms runs in the area of the joints of the other mechanism, undesired vibrations are generated.
The patent application US2001/0053874 describes an endoscope comprising a distal terminal portion, of movable type, and an operating device, which is operatively connected to the distal terminal portion, to operate the latter. The patent application US 2011/0295065 describes a segmented instrument having an elongated body, which includes a plurality of connections and a hinge which connects a pair of adjacent connections of said plurality of connections. Lastly, the U.S. Pat. No. 6,036,636 describes an endoscope including an elastic member, which connects a distal terminal portion of an insertion portion to a proximal terminal portion of a tip portion, so as to form a space portion. A wire extends from the tip portion to a proximal side of the insertion portion and is curved in the space portion.